iPS

Monitoring the Undifferentiated Stage of Stem Cells—the Pluripotency Markers

Human embryonic stem (ES) cells or induced pluripotent stem (iPS) cells promise to serve as an unlimited source for transplantation or tissue-specific differentiation. However, obtaining and maintaining stem cells are very difficult tasks for multiple reasons. For instance, most stem cell lines tend to spontaneously differentiate in culture, and even if the cells form stem cell-like colonies, they may be of a heterogeneous population.

To identify pluripotency of stem cells, expression of stem cell-specific marker genes (i.e. Oct-3/4, Sox2, Nanog, Rex-1) is monitored by RT-PCR. Alkaline phosphatase activity and methylation profiles of promoters of pluripotency-relevant genes are often analyzed as well. Compared to murine cells, it is noticeably more difficult to obtain human iPSCs, of which stem cell-like colonies sometimes turn out not to be pluripotent cells. We highly recommend testing iPSCs, especially human iPSCs, with antibodies against stage-specific embryonic antigens such as SSEA-3, SSEA-4, TRA-1-60, and TRA-1-81.

However, all of these methods require cell destruction or fixation for analysis, therefore, are inconvenient and costly. Furthermore, many studies using ES or iPS cells involve differentiation of stem cells into different lineages, a method for observing live cells to know their undifferentiation/differentiation stages would be very helpful. There have been a number of publications using murine Oct-4, Nanog, and Rex-1 promoter driven fluorescent proteins as markers for pluripotency tests [1-3]. Allele Biotech provides, under its iPS product line, packaged and validated lentiviral particles that would insert these 3 promoter-FP reporters into the stem cells. Although currently these promoters are of mouse sequences, their use in human stem cells have been reported.

    New product of the week 01-25-10 to 01-31-10:

All-In-One-Vector: Human OSKM Lentiviral Paticles, with Oct-4, Sox-2, Klf, and c-Myc all expressed from a single virus, ready-to-use.

      Promotion of the week:

human iPS cell detection primer set, the same as the landmark Yamanaka paper [4] on creating human iPS for the first time.

1. Da Yong WU, Zhen YAO (2005). Isolation and characterization of the murine Nanog gene promoter. Cell Research, 15 (5): 317–324.
2. Rachel Eiges, Maya Schuldiner..et.al (2001). Establishment of human embryonic stem cell?transfected clones carrying a marker for undifferentiated cell. Current Biology 11: 514–518.
3. Guangjin Pan, Jun Li, Yali Zhou, Hui Zheng, and Duanqing pei (2006). A negative feedback loop of transcription factors that control stem cell pluripotency and self?renewal. ASEB Journal 20: E1094? E1102
4. Takahashi et al, Induction of Pluripotent Stem Cell from Adult Human Fibroblasts by Defined Factors (2007). Cell 131, 861-872

Tags: , , , , , , , , , , ,

Thursday, January 28th, 2010 iPS and other stem cells No Comments

Allele Pre-packaged, Titer-determined, Validated iPS Generating Lentivirus Particles

Induced pluripotent stem cell (iPSC) has been an important research area in the past 3 years. These cells have also provided unprecedented possibilities to study cell differentiation and tissue development to biologists in many fields. Allele pre-packaged iPS lentiviral particles are validated, ready-to-use, high quality reagents for any laboratory to create iPS cells. A straight-forward and optimized protocol is also provided for immediate use of these products. iPC cells can be produced typically in 2-3 weeks; but when used in combination with shRNA against p53 (also available from Allele), iPSCs can be produced in just about 5 days!

Follow iPS news on our news page.

Tags: , , , , , , ,

Why Allele?

Allele provides you with tools that you will find very helpful.  The two main motives for Allele developed products are:
1) To incorporate the most advanced technologies in the field
2) To provide equal utility as other companies’ equivalent products at a much more reasonable cost.

How did we do it?        By developing technologies internally, in most cases with government grant funding, by in-licensing others’ discoveries, and by listening to you, our customers.

What else do we do?      Conduct basic curiosity-driven research just like most of our customers. It helps to stay on the edge and connect to the community.

Tags: , , , , , , , , , , , ,

Tuesday, July 28th, 2009 Customer Feedback, Open Forum No Comments

Allele Mail Bag: Our discovery that stem cells and other cells can be non-invasively intranasally delivered to the brain.

A few words from the blog editor:  The Allele Mail Bag is a new feature we initiated here by this post on July 20, 2009.  We like to post some of the messages that our research, business development, or customer service staff receives through Allele’s published email boxes, e.g. oligo@allelebiotech.com (for ordering any product or service), iPS@allelebiotech.com, RNAi@allelebiotech.com, FP@allelebiotech.com, Vivec@allelebiotech.com (for consulting with Allele experts on each of the focus product group. FP: fluorescent proteins.  Vivec: viral vectors).  If we find your message to be suitable as a guest post on our blog, we will ask for your permission first.

In addition to any questions about any product, service, or R&D activity that Allele may provide or perform, we also encourage you to use our communication and social networking channels to help more people become aware of your own research progress.  After all, it is by the same principle of scientific information exchange through traditional channels such as publication in journals or presentation at meetings—the better we communicate the more science benefits.

Excerpt from a recent email to iPS@allelebiotech.com, with permission from Dr. Frey:

“Hi,
I am excited to tell you that along with my collaborators in Germany, especially Lusine Danielyan MD, I have discovered that stem cells and other therapeutic cells can be non-invasively delivered to the brain using the intranasal delivery method that I developed.  The first of our papers on this new discovery was just published in European Journal of Cell Biology.  I have attached a copy of this paper.  I am hopeful that this    breakthrough, that could revolutionize the stem cell industry and make stem    cell treatments practical by eliminating the need for invasive neurosurgical implantation of cells, can facilitate the development of stem cell therapies for Parkinson’s disease, Alzheimer’s disease, stroke, traumatic brain injury and many other brain disorders.

Best Regards,

William H. Frey II, Ph.D., Director
Alzheimer’s Research Center
Regions Hospital
640 Jackson St.
St. Paul, MN 55101
Professor of Pharmaceutics, Neurology
and Neuroscience
University of Minnesota”

Tags: , , , , , , , , , , ,

iPS- #1 Breakthrough of 2008 Now at Allele!

Hailed as Science Magazine’s “#1 Breakthrough of the Year” for 2008, induced pluripotent stem (iPS) cell research is proving to be the most promising means of worldwide disease comprehension and eradication since the discovery of penicillin. iPS research is moving fast and institutions are racing to make the coveted advancements to: reveal the triggering and oppressing mechanisms of the four pluripotency inducing genes, elucidate how a cell is assigned a role by investigating cell protein signaling pathways, and reduce possible side effects like cancerous tumors at iPS cell therapy sites. As an in vitro reagent, iPS cells, unlike human cell lines, can be easily maintained in the lab. By maintaining iPS cell lines from patients with diseases like Parkinson’s it is possible for researchers to examine disease pathology in an affected living cell in ways that cannot be done with in vivo cells. Thanks to induced pluripotency, these cell lines can be created with simple, non-invasive hair follicle procurements! Additionally, juxtaposed to the 10 years of controversy following the discovery of human embryonic stem cells, induced pluripotent stem cells will not elicit the same moral or bioethical dilemmas followed by political interference due to their fully developed origin.

Author of Breakthrough of the Year: Reprogramming Cells, Gretchen Vogel stated, “…several more breakthroughs are needed before cellular reprogramming yields its first cure for disease.” Researchers must take advantage of Allele Biotech’s ground-breaking iPS product line. Our scientists have done all the preliminary work to design and construct these easy to use iPS kits to make this phenomenal field of study accessible to all. The global challenge for iPS discovery has begun!

Tags: , , , , , , , ,

Friday, April 17th, 2009 iPS and other stem cells No Comments